Time controlled selector apparatus for radio receivers



June 20, 193 o. A. CARLSON ET AL TIME CONTROLLED SELECTOR APPARATUS FOR RADIO RECEIVERS Filed June 16, 1936 4 Sheets-Sheet l OS'mrA. czrlaarz/ Zaaz'a Pratt INVENTORS ATTO RNEYS WITNESS 1939- o. A. CARLSON ET AL 2,153,199

TIME CONTROLLED SELECTOR APPARATUS FOR RADIO RECEIVERS Filed June 16, 1936 4 Sheets-Sheet 2 0 oscarAar-lsom Q Louis Pra tt INVENTORS WITNESS ATTO RNEYS June 20, Q, A, CARLSQN ET AL TIME CONTROLLED SELECTOR APPARATUS FOR RADIC RECEIVERS Filed June 16, 1936 4 Sheets-Sheet 3 ATTORNEYS WITN E55 June 20, 193g. o CARLSON ET AL TIME CONTROLLED SELECTOR APPARATUS FOR RADIO RECEIVERS Filed June 16,, 1936 4 Sheets-Sheet 4 Rwer Fae/Z 0.904114 arisen loam fi'w 'NVENTORS WITN E55 ATTORNEYS Patented June 20, 1939 UNETED STATES PA'EENT E'FEQE Oscar A. Carlson and Louis Pratt, Detroit, Mich.

Application June 16,

9 Claims.

The object of the invention is to provide a time controlled selector apparatus for radio receiving sets by means of which the set may be automatically turned on at predetermined time intervals and in tune with a preselected station; to provide an appliance of the kind indicated in which the clock or time mechanism is incorporated as an element of the apparatus or appliance; to provide an automatic selector apparatus in which the tuning element, when set in operation, is continuously moved the entire extent of its prescribed movement and automatically stopped at the selected point approximately at resonance with the selected station and thereafter moved the minute distance that may be necessary to effect complete resonance; to provide an apparatus of the kind stated in which the actuating elements may be readily set to their desired position with a minimum of skill on the part of the user; to provide a construction in which the actuating elements are simultaneously shifted to their inactive positions previous to a resetting; and generally to provide a time controlled radio receiving set selector apparatus which may be incorporated in conventional sets and which, for the functions to be performed, is of comparatively simple form with the possibility of disarrangement of parts reduced to a minimum.

With this object in view, the invention consists of a combination and arrangement of parts of which a preferred embodiment is illustrated in the accompanying drawings, wherein:

Figure 1 is a front elevational View of the invention.

Figure 2 is a sectional view on the plane indicated by the line 22 of Figure 1.

Figure 3 is a top plan view of the tuning element and its attendant actuating devices and control.

Figure 4 is a sectional view on the plane indicated by the line 5-4 of Figure 2.

Figure 5 is a rear elevational view, partly broken away, of the switch actuating drum and time echanism.

Figure 6 is a rear elevational view of the tuning element.

Figure 7 is a detail sectional view of the switch drum driving mechanism.

Figure 8 is a longitudinal sectional View illustrating the connection between the switch drum and its shaft.

Figure 9 is a perspective view of the contact traveler actuated by the tuning element.

1936, Serial No. 85,602

Figure 10 is a sectional view on the plane indicated by the line Iii-10 of Figure 6.

Figure 11 is a sectional View on the plane indicated by the line i l-l l of Figure 5.

Figure 12 is a detail view, partly in section and partly in elevation, illustrating one of the drum actuated switches.

Figure 13 is a diagrammatic view illustrating the control circuit.

Figure 14 is a sectional View on the plane indicated by the line E i-M of Figure 2.

The primary actuating means of the apparatus constituting the invention consists of a drum in the form of a squirrel cage and driven in time relation with a clock or time controlled mechal5 nism. The drum is composed of the head and tail disks and 2! and the rods 22 which span the isks and which are uniformly spaced therearound, there being in the illustrated embodiment forty-eight rods, which, as hereinafter appears, provides for switch actuating movement at fifteen minute intervals if desired. The tail disk 2! is formed with a hub 23 through which is threaded a screw 24, the latter engaging in a slot or keyway 25 in a shaft 23, the shaft constituting the ifi driving and supporting element of the drum and being journaled in the rear and intermediate cross bars 27 and 28. The slot or keyway 25 provides for relative axial movement of the shaft and drum but precludes relative angular or turning movement of the two.

A compression spring 29 surrounds the shaft 26 and is compressed between the cross bar and the head disk so that the time hub of the tail disk is maintained in end abutting engagement with the cross bar 21. By this means, a too free turning movement of the drum is precluded which is desirable in order to make the drum positive in its switch closing function.

A shaft 26 also passes through and is journaled in the forward cross bar3t and between this latter and the intermediate cross bar 28 carries a collar 3| between which and the cross bar 30 there is disposed a compression spring 32 which functions to yieldingly impel the shaft axially in the direction of the drum, so as to maintain the clutched relation of the shaft and gear 33 which is loosely mounted on a hub 34 secured to the cross bar 30 by the sleeve extension 34a which has a force fit in the cross bar. The gear 33 may rotate freely on the hub except when it is engaged with the coupling pin 35 carried by the arm 38 which is secured to the shaft 26. The gear 33 is formed with a perforation 31 (Figure 4) to receive the pilot extremity of the coupling pin and .ward movement, the dial is brought up just behind the fixed pointer 43, so that in the uncoupling operation of the shaft, the latter and with it the drum may be rotated to position any one of the bars 22 at a point for setting its switch.

actuating cam which is carried thereby.

The switch actuating cams which are carried by the rods 22 are in the form of small cylinders 4| which are slidably mounted on the rods and provided with friction springs 42, bearing on the.

rods on diametrically opposite sides of the latter.

' Any cam may be moved longitudinally of its rod to any desired position in the length of the drum to be in the path of one of the control switches 43 of which there are a plurality mounted on the base 44, the control switches being spaced from each other but arranged side by side at one side of the drum. In inoperative position, the switch cams occupy positions adjacent the forward disk 24 and each is advanced to its desired position on its attendant rod when the drum is turned to position a selected cam in the path of a finger 45, the shaft being pulled forward to declutch it from the drive gear 33, when this setting function of the cam is to be performed.

' The finger 45 is mounted on a slide 46 movable over guide rods 41 mounted in spaced standards 48 carried by the base 44 andtheslide is advanced in the direction of the rear disk 22 by applying a pull to a cable 49 of which one end is anchored to the slide and the other end secured to a drum 50 on which the cable is reeled after being carried around a direction sheave 5|. The drum 50 is carried at the rear end of a shaft 52 'journaled in bearings in standards 53 mounted on the base 44. The shaft is provided at the forward end with a turning knob 55. The slide 46 is moved toward the forward disk when the cable 49 is unreeled,.this action being accomplished by means of a tension spring 56' of which one end is anchored to the upright 57 and the other to an indicator slide 58 to which a cable 59 is secured, this cable 59 being carried around a direction pulley 6E and terminally secured to the slide 46. The indicator slide 58 carries an indicator 6| movable over the scale 62 on which the indications are spaced to accord with the spacing between the switches 43. Thus, when the knob is turned, the indicator 6!! moves over its scale the distance which a particular cam is advanced by the finger 45. which switch a particular cam is advanced for the actuation of that switch. On release of turning movement on the knob 55, the spring returns the indicator 3| to the left end of the scale 62 and returns the slide to its position adjacent the forward disk 20 preparatory to setting the next cam, the cable 49 being unreeled from the drum 5| in this operation. 7

During the cam setting operation, the shaft 26 is held in its forwardly advanced position to leave the drum and shaft free of the gear 33 while the latter is being continuously turned by the clock mechanism which is of conventional construction except to provide for the actuation of additional The indicator thus shows to.

elements necessary to carrying out the function of the invention.

The clock motor is housed in a case 63 driving the second, minute and hour spindles through appropriate gearing designated generally at 64 and including a gear 65 in mesh with the gear 33, as well as a gear 66 which drives a pinion 67 which makes a revolution for every revolution of the second hand 68. The pinion 6'! drives a spindle 69 terminally formed with a crank 10 which intermittently turns the star wheel I I, this latter being formed with fifteen teeth between which the crank engages to advance it a fifteenth of a revolution for each revolution of the crank. The star wheel thus makes one complete revolution every fifteen minutes and one of its teeth 12 is of greater radial extent than the others, so

that once. in each revolution it may engage the springfinger 13 to shift the lower arm of the switch 'l4 into circuit closing position, the switch consisting of complemental contact elements mounted on insulating plates secured together by a bowed spring 15 which normally impels the contact points away from each other, so that they are spaced or in open'circuit position except when the tooth 12 engages the finger 13. The star wheel 12 is mounted back of the dial 16 but is operatively connected with an indicator H exposed on the front of the dial and traversing a dial of its own to show the position of the star Wheel at any indicated time.

A finger crank 18 formed at the extremity of the shaft 19 is provided for manually setting the star wheel when desired to bring it in time with the clock mechanism in the event of any loss in the timed relation of the parts. A spring provides the necessary friction to prevent free turning of the shaft 19 and an actuating crank 81 is formed at its rear extremity to provide for finger actuation.

Means areprovided for returning the switch camstotheir inoperative position adjacent the forward disk 20 preparatory to any resetting operation of' the cam and these means comprise a ring 82 surrounding thedrum and normally disposed adjacent the rear disk 22, and a pull shaft 33 of which the rear end is connected with a pendent plate 84 carried by the ring and the forward end is mounted in a bearing in the standard 85. The plate 84 is formed with a flanged foot- 86 which traverses guides 81 mounted on the base 44. A knob 88 is carried at the forward extremity of the shaft 83 to provide for pulling and pushing of the latter to move the ring 82 forwardly toward the front disk 23 or to return it to its normal position adjacent the rear disk 2|. The ring, while surrounding the drum, is not in contact with the rods thereof by reason of the mounting of the foot portion of the plate 24 in the guides 81.

The tuning element which may be either a vari able capacity or a variable inductance is housed in a case 89 and its rotary element is mounted on the shaft 90-journaled in appropriate hearings in the end walls of the case and provided with a forward exterior turning knob 91 by means of which manual adjustment is afforded but in such case only for making initial settings unless it is desired totune the set to some station for which provision has not been made for automatic setting.

Theautomatic setting of the tuning element is accomplished through the instrumentality of an electric motor 92 which through a gear reduction housed. inthe base 93 drives an upstanding worm shaft 94, at the upper end of which is carried the worm 95. The motor base is set on a cushioned mounting 96, of rubber or its equivalent, to kill any noises from vibration.

The worm 35 meshes with the worm wheel 91 rotatably mounted on a standard 98 carried by the base 93. This worm wheel is provided with an eccentric pin 39 with which one extremity of the rack bar I is pivotally connected. The teeth of the rack bar mesh with the teeth of a pinion IUI which is mounted on the shaft 90 but floats on the latter except when it is clutched with the same which is accomplished by bringing it laterally into contact with the collar I82 which is provided with a friction face next to the gear to effect a frictional connection between the two. A rack guide IE3 is mounted on the end wall of the case 89 to guide the far end. of the rack and the latter is kept in close engagement with the pinion by means of a tension spring I64. It is obvious that rotation of the worm wheel will efiect oscillatory movement of the pinion and if the latter be clutched to the shaft 90 will effect corresponding movement of the rotary member of the tuning element. This oscillatory movement is designed to be the complete arc of movement of which the rotary member of the tuning element is susceptible.

The pinion is moved into and out of clutch engaging movement with the collar I52 by means of a shifter I55, pivotally mounted, as indicated at I33 and the shifter is normally impelled in a direction to effect declutching by means of a compression spring i! compressed between one face of its force arm and the front wall of the case 89. The shifter is rocked into clutch engaging position by means of an electro-magnet I88, of the long range form, whose core 559 is connected by means of a spring H3 with the extremity of the force arm of the shifter. When the magnet is energized, clutch engaging position of the pinion is efiected. But the magnet Hi3, aside from effecting clutching operation, also eilects switch opening operation, the core I59 being provided with a stem I II adjacent the extremity of which is a collar I I2 which engages one arm of a switch H3, this switch being similar to the switch I4 but normally held in closed position and shifted to open position by the engagement of the collar H2 with the longer arm when the magnet is effecting clutching operation of the pinion.

The motor 92 and the magnet I08 are connected in parallel, so that they are simultaneously energized, as hereinafter appears.

The tuning element, on that end of the shaft which projects from the rear of the element, carries a disk H4 which is provided with a slot H5 adjacent its periphery but of an angular extent slightly in excess of 180". This slot is provided for the mounting on the disk of the latch blocks H3 of which there is one for each of the switches 43 when the full complement of switches are employed or less if there is less than the full complement of switches used. Each latch block, on its rear face, has a boss I I! which enters the slot and which is so shaped on its edges as to insure the block having a radial position on the disk. Each block is locked in its desired position on the disk by means of the screw bolt H8 and its attendant nut. On the outer end each block is formed with a V-shaped notch H9 constituting a seat for the latch arm. Secured to the case 89 and with its circular portion concentric with the disk H4 is a contact yoke I20, this being preferably metal but enclosed by a soft rubber tubing, so that when the contact clamps IZI are attached, they may compress the covering to make an unobstructed track over which the roller I22 of the contact traveler may pass, the contact traveler consisting of a block of insulating material I23 secured to the disk and carrying the roller at the extremity of a metal yoke I24 mounted in the block and having a loop I25 on the top to which a pigtail connector may be secured. The contact clamps I2I are positionable at any point on the yoke I at which it is desired to bring the movable member of the tuning element to rest. When the contact traveler roller engages the contact element, it will under certain conditions hereinafter explained stop the movement of the movable member of the tuning element but this will be only at approximate resonance of the station being tuned in. shifting of the movable member is accomplished by the engagement of the out-turned end I of the arm I21 with the V-shaped notch or seat in the corresponding latch block H5.

The arm I21 is formed as an extension of the shaft I23 which passes through the tuning element and is journaled in the front and back walls of the casing 89 and is formed at the front of the tuning element with a Z-shaped arm I29 of which the free extremity is connected with the core I30 of a long range electro-magnet I3I, the connection between the arm and magnet core being by means of a tension spring I32. Normally the arms I21 and I29 are elevated until the latter abuts the stop I33, when the extremity 25 of the arm I20 is free of the latch blocksthat is, out of invading position of the path of movement of the latch blocks. Elevation of the arms is effected by means of a tension spring I34. When the arms are moved downwardly, as they will be when the magnet I3I is energized, the Z-shaped arm engages and opens the switches I and I36, both of which are carried on an insulating block I31 mounted on the front wall of the case 89. The switches I35 and I33 each consist of dual spring blades normally in circuit closing position but moved to open position by the depression of one blade at each. The switch I35 is in series with the motor 92 and magnet I03 and the switch I35 in series with the switch II3.

A contact I2I is provided for each of the switches 43 and is electrically connected therewith by a conductor I38.

Each of the switches 43 consists of an upstanding spring strip secured to the base 44 and provided with an angular extremity I39 with which the cam rolls may engage and between the switches and the squirrel cage drum there is mounted a guard I43 which is secured to the base and spans the full complement of switches, so as to limit their inward movement and preclude any vibration after the angular extremities I39 leave the cam rolls. The conductors I38 are connected to contact strips M! which are mounted on insulating strips I42 which are carried by the switch members 43. When the switch members 43 are cam actuated, the contact strips I4! bridge the conductor bars I43 and I44 which are arranged in spaced parallel relation and terminally mounted in insulating blocks I45 which carry stems I46 slidably mounted in standards I41, compression springs I48 surrounding the stems and being compressed between the blocks Final and the standard; By this construction the whole conductor bar assembly is made yieldable.

The power pack I49 is connected'across the line in series with the switches II3, I36 and I50, the latter being a main control switch. The clock motor is connected across the line independent of any switch in the apparatus. The magnet I3I is connected in series with the contact traveler I22 and the'switch 14 in series with the contact bar I44.

In the use of the invention, the first operation is the setting of the drum cams to effect operation of the radio receiver at the desired times to bring in selected programs. To accomplish this, the drum is declutched from the clock mechanism which, as above explained, is accomplished by pulling the shaft 26 forwardly to disengage the pin 35 from the gear 33. This position of the shaft is maintained by a continued pull in opposition to the pressure of the spring 32 but the drum may then be rotated until an indication on the dial 39 which corresponds to the time that the selected program is put on the air is behind the pointer 40. This will position the proper rod 22 at a point where its cam roll will be directly behind the finger 45. Turning of the knob 55 will then advance the cam roll along the rod until it is disposed in the vertical plane of the switch member 43 which corresponds with the desired station and which is indicated by the pointer GI on the scale 62. This operation is repeated for the various programs desired to be brought in. The shaft 26 isthen recoupled with the gear 33 by releasing the pull on the knob 38 and the subsequent rotation of the shaft until the pilot of the pin 35 enters the opening or hole 31 in the gear. The apparatus is then set for automatic operation.

The star wheel II is rotated in a step-by-stepmovement and completes a revolution once in each fifteen minutes and when the extended tooth 12 engages the switch 14 and closes the same, the current will flow from the supply line to the binding post I52, thence over the conductor I53, through the switch 14, and the conductor I54 to the conductor bar I44. When a cam roll engages a switch member 43, it will cause that switch memberscontact plate I4I to bridge the conductor bars I44 and I43, sothat current, having reached the conductor bar I43, will flow over the conductor I55 to the switch I35, thence over the conductor I56 and through the motor 92 and magnet I08 in parallel, returning to the other side of the supply line through the conductor I51, and main switch I50 and binding post I5I B energizing the magnet I08, as above explained, will result in its opening the switch I I3. But the motor will be energized, and the tuning element will thereby be oscillated back and forth, since energizing the magnet I08 effects operation of the shifter I05 and the clutching of the pinion ml with the tuning element. The movement imparted to the tuning element by the motor may be the full arc of movement of the tuning element, or it may be less, depending on what takes place with respect to the traveler I22 and any one netI3I and to' the binding post I 5I over'the conductor I51. This will result in energizing the magnet I3I which, as above explained, effects a pull on the Z-shaped arm of the shaft I28 bringing the extremity I26 of its arm I21 into the V- shaped seat II9 of the block II6, the block having been previously set for the proper position of the tuning element for the particular station. The approximate position of the tuning element was obtained when the traveler roll engaged the particular contact I2I and the minute movement necessary is effected by the out-turned end'of the arm I21 engaging the seat in the block.

When the magnet I3I actuated the Z-shaped arm I29, it engaged and operated the switches I 35 and I36 and since the switch I35 is in series with the motor and magnet I08, its opening resulted in depriving both of these of current, so that the motor is brought to rest and the pinion'IOI is declutched from the tuning element, sorthat the tuning element may be moved the minute distance necessary to allow the out-turned extremity of the arm I21 reaching the bottom of the V-shaped seat in the engaged block I I6.

But de-energizing the magnet I08 resulted in closure of the switch I I3, although the power pack I49 is still deprived of current, since the switch I 36which is in series with'the switch I I3 is open at this instant.

The star wheel 1I having once operated the switch 14, it will retain the switch in closed posi-- tion for one minute at least and'that interval of time is necessary for the above described cycle of operations to take place. When the lengthed tooth 12 of the star Wheel has been driven past the switch operating point, however, the switch 14 is opened and since all of the energizing current for the apparatus except that employed to actuate the clock, must pass through this switch, the opening of said switch deprives the magnet I3I of the current, so that its core is released and the arms I21 and I29 of the shaft I28 are elevated and the switches I35 and I36 returned to closed position. But no other parts of the apparatus than the power pack are then placed in circuit, current for the latter flowing from the binding post I52 over the conductor I60, through the power pack, over the conductor I6I through'the switch II 3, over the conductor I62, the switch I36 and the conductor I63, thence to the other side of the line through the binding post I5I.

Provision is made for the automatic cuttingout of the apparatus at a twelve hour period after the setting of the drum cam. This cut-out is in the form of a switch I64 which is. interposed in a the conductor I54 and which comprises compleposition unless pressure be applied to the longer arm to separate it from the shorter arm. The switch I64 is supported from an insulating block I65 projecting from the clock frame which is carried on the bar 30.

The switch opening means comprises a disk I66 mounted upon the shaft 26 but rotating free of the latter and being provided with a hub I61 which abuts the front face of the cross bar 28. A flexible member I68 is reeled on the hub I61 and is terminallyconnected' with a leaf spring I69 which is anchored to the base 44. When the flexible member is reeled on the hub, as it is when the disk I66 is clutched to the shaft 26, the spring I69 is sprung laterally, so that sufficient energy is restored-to rotate the disk in the opposite direction when the driving connection is released. The driving connection between the disk I66 and the shaft 26 is effected through the collar 35 which on that side facing the disk is provided with a friction face I'EB. When the drum is coupled to the shaft 26 through the arm 36, the friction face ill engages the disk and thus rotates it in the direction in which the shaft is moving. After a, complete revolution of the drum, the finger ll! carried by the disk is brought into engagement with the longer arm IBM of the switch 164 and the pressure thus applied to the arm swings its contact away from the contact of the other arm and thus effects switch opening movement. The finger Ill is pivotally mounted in a V-shaped notch H2 in the disk I68 and may swing from one side to the other of the disk. This control is provided to allow for the finger thickness in permitting the disk to make a complete revolution. After the finger contacts with the switch arm, the switch is kept in open position by the sliding of the disk against its frictional connection with the collar. Switch closing movement may be effected by declutching the drum from the shaft 26, when the spring IE9 becomes active to rotate the disk in the opposite direction until the finger ll! is brought up against the opposite side of the arm 56 3c. Thereafter, the drum must make a complete revolution which is accomplished over a period of twelve hours before switch opening movement is again effected.

The invention having been described, what is claimed as new and useful is:

1. A time controlled selector apparatus for radio receivers comprising a tuning element, means for oscillating the tuning element through its full arc of movement, a plurality of switches operatively connected with the tuning element to set the same in motion and stop it in preselected positions, a time controlled mechanism, and a drum positively driven by the time mechanism and embodying a plurality of uniformly spaced peripherally positioned longitudinally arranged rods, a cam slidably mounted upon each rod, 2. finger arranged tangentially of the drum, and means for moving the finger laterally to traverse in a direction longitudinally of the drum, the drum being releasable from the time mechanism to manually position any cam in the path of movement of said finger for adjusting cams along the rods to so position them as to have one engageable with each of said switches to move the same to circuit closing position 2. A time controlled selector apparatus for radio receivers comprising a tuning element, means for oscillating the tuning element through its full arc of movement, a plurality of switches operatively connected with the tuning element to set the same in motion and stop it in preselected positions, a time controlled mechanism, and a drum positively driven by the time mechanism and embodying a plurality of uniformly spaced peripherally positioned longitudinally arranged rods, a cam slidably moiuited upon each rod, a finger arranged tangentially of the drum, and means for moving the finger laterally to traverse in a direction longitudinally of the drum, the drum being releasable from the time mechanism to manually position any cam in the path of movement of said finger for adjusting cams along the rods to so position them as to have one engageable with each of said switches to move the same to circuit closing position, said means embodying an indicator to determine definitely the position of the cams in the adjusting operation.

3. A time controlled selector apparatus for radio receivers comprising a tuning element, means for oscillating the tuning element through its full arc of movement, a plurality of switches operatively connected with the tuning element to set the same in motion and stop it in preselected positions, a time controlled mechanism, a drum positively driven by the time mechanism and having a declutchable connection with the same, a dial operatively connected with the drum to move in unison with the latter, the drum comprising a plurality of uniformly spaced peripherally arranged longitudinal rods and cams carried one by each of said rods, a finger arranged tangentially of the drum, a slide mounted to travel in the direction of the length of the drum and supporting the finger, and manual means for imparting movement to the slide, any cam in a certain position of the drum being in the path of movement of the finger to effect adjustment of the cam along its attendant rod for operation of any of said switches to move the same to circuit closing position.

4. A time controlled selector apparatus for radio receivers comprising a tuning element, means for oscillating the tuning element through its full arc of movement, a plurality of switches operatively connected with the tuning element to set the same in motion and stop it in preselected positions, a time controlled mechanism, a drum positively driven by the time mechanism and having a declutchable connection with the same, a dial operatively connected with the drum to move in unison with the latter, the drum comprising a plurality of uniformly spaced peripherally arranged longitudinal rods and cams carried one by each of said rods, a finger arranged tangentially of the drum, a slide mounted to travel in the direction of the length of the drum and supporting the finger, and manual means for imparting movement to the slide, any cam in a certain position of the drum being in the path of movement of the finger to efiect adjustment of the cam along its attendant rod for operation of any of said switches to move the same to circuit closing position, the said manual means comprising a drum, a flexible member secured to the slide and trained around the drum, a shaft for rotating the drum and a finger knob attached to the shaft.

5. A time controlled selector 1. aratus for radio receivers comprising a tu: cg element,

means for oscillating the tuning element through its full arc of movement, a plurality of switches operatively connected with the t ing element to set the same in motion and stop it in prcselection positions, a time controlled mechanism, a drum positively driven by the time mechanism and having a declutchab-le connection with the same, a dial operatively connected with the drum to move in unison with the latter, the drum comprising a plurality of uniformly spaced peripherally arranged longitudinal rods and cams carried one by each of said rods, and means for simultaneously shifting all oi said c ns to a position free of engagement with said switches, and embodying a ring encircling the drum but out of contact with the rods thereof and a pull rod connected with said ring.

6. A time controlled selector apparatus for radio receivers comprising a tuning element, a motor operatively connected with the tuning element to drive the same through its full arc of movement, a clutch embodied in the connection between the motor and the tuning element, a pair of parallel conductor bars, a plurality of spaced switches disposed in facing relation to said conductor bars but normally spaced therefrom, a time mechanism, a member positively driven by the time mechanism and provided with selectively adjustable elements to engage any of said switches and move them into bridging relation with the conductor bars, one of said conductor bars being in circuit with a source of supply and the other in circuit with the motor, a cut-out for the motor, a plurality of switches actuated by the tuning element and operatively connected with the first said switches, and clutch actuating means controlled by the first said switches and the cut-out.

7. A time controlled selector apparatus for radio receivers comprising a tuning element, a motor operatively connected with the tuning element to drive the same through its full arc of movement, a clutch embodied in the connection between the motor and the tuning element, a pair of parallel conductor bars, a plurality of spaced switches disposed in facing relation to said conductor bars but normally spaced therefrom, a time mechanism, a member positively driven by the time mechanism and provided with selectively adjustable elements to engage any of said switches and move them into bridging relation with the conductor bars, one of said conductor bars being in circuit with a source of supply and the other in circuit with the motor, a cut-out for the motor, a plurality of switches actuated by the tuning element and operatively connected with the first said switches, and clutch actuating means controlled by the first said switches and the cut-out, the cut-out and the clutch actuating means embodying coordinated radio control switches.

8. A time controlled selector apparatus for radio receivers comprising a tuning element, a motor operatively connected with the tuning element to drive the same through its full arc of movement, a clutch embodied in the connection between the motor and the tuning element, 2.

pair of parallel conductor bars, a plurality of spaced switches disposed in facing relation to said conductor bars but normally spaced therefrom, a time mechanism, a member positively driven by the time mechanism and provided with selectively adjustable elements to engage any of said switches and move them into bridging relation with the conductor bars, one of said conductor bars being in circuit with a source of supply and the other in circuit with the motor, a cut-out for the motor, a plurality of switches actuated by the tuning element and operatively connected with the first said switches, and clutch actuating means controlled by the first said switches and the cut-out, the cut-out and the A clutch actuating means embodying serially connected radio control switches moved to open position when said cut-out and means are actuated.

9. A time controlled selector apparatus for radio receivers comprising a tuning element, a motor operatively connected with the tuning element to drive the same through its full arc of movement, a clutch embodied in the connection between the motor and the tuning element, a

pair of parallel conductor bars, a plurality of spaced switches disposed in facing relation to said conductor bars but normally spaced therefrom, a time mechanism, a member positively driven by the time mechanism and provided with selectively adjustable elements to engage any of said switches and move them into bridging relation with the conductor bars, one of said conductor bars being in circuit with a source of supply and the other in circuit with the motor, a

cut-out for the motor, a plurality of switches actuated by the tuning element and operatively connected with the first said switches, and clutch actuating means controlled by the first said switches and the cut-out, the cut-out and said means embodying serially connected radio con- .5

trol switches moved to open position when said cut-out and means are actuated, and a main control switch periodically actuated by the time mechanism.

OSCAR A. CARLSON. LOUIS PRATT. 

